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Effects Of Acquisition System Parameters On Refraction Survey Data
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 5th EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, Apr 1992, cp-210-00023
Abstract
The seismic refraction method is ideal for a variety of applications where large<br>features that are characterized by an abrupt increase of the seismic velocity need to be<br>delineated, such as the depth to the water table or the depth to basement rock. Over the<br>years, the techniques used to acquire and process seismic refraction data have changed<br>slowly. Most of the current techniques used for refraction processing were developed from<br>the late 1930’s to the early 1960’s (e.g., Hagiwara and Omote, 1939; Hagedoorn, 1959;<br>Hawkins, 1961). The most recent advance in seismic refraction processing, the Generalized<br>Reciprocal Method, was first published in 1980 (Palmer, 1980). Since the early 1970’s,<br>computer programs have been developed to facilitate processing of seismic refraction data<br>(e.g., Scott and Markiewicz, 1990). Most of these programs have merely changed the<br>processing platform from drafting boards to computer monitors with little modification to<br>the processing procedures.<br>The most recent developments for the refraction method have involved the data<br>acquisition systems. Features such as analog and digital filtering, IFP, and automatic gain<br>setting have become standard on many seismic data acquisition systems. These features<br>have made recording systems easier to operate and the recorded seismic traces appear to<br>be more robust. The results of theoretical calculations, numerical model studies, and field<br>tests, however, demonstrate the need to fully understand how changes to the acquisition<br>system settings affect the first break signal.